1. Input of acid deposition to forests(1) Input of acid deposition to forests was observed at various environments(2) Observation of dry deposition was started2. Throughfall, stem flow and soil(1) Seasonal fluctuations and difference in tree species were examined on pH, EC and dissolved ion(2) Neutralization process of acid deposition was examined on stands of Japanese cedar, Japanese cypress and so on(3) Reaction of plants and changes in vegetation were examined in relation to changes in soil environment3. Stream water's characteristics(1) Stream water's characteristics were examined at several watershed(2) Process of mineral output from forests was examined(3) Changes in water characteristics and mineral expenditure, were examined at snowy region in relation to snowmelt4. Methods for collecting depositions(1) Methods for collecting throughfall and stem flow were rediscussed(2) Methods for collecting dry deposition and soil solution were discussed(3) working group were organized to discuss methods for collecting depositions(4) Manual was made for acid deposition's observation5. Simultaneous observations(1) Simultaneous observations of wet deposition, dry deposition, throughfall of Japanese cedar, stem flow and stream water were conducted6. Data base(1) Methods for creating data bases from data collected in this research were discussed(2) Data base was created using data of simultaneous observations